Postal is an open source SMTP server. Postal versions less than 3.0.0 are vulnerable to SMTP Smuggling attacks which may allow incoming e-mails to be spoofed. This, in conjunction with a cooperative outgoing SMTP service, would allow for an incoming e-mail to be received by Postal addressed from a server that a user has 'authorised' to send mail on their behalf but were not the genuine author of the e-mail. Postal is not affected for sending outgoing e-mails as email is re-encoded with `<CR><LF>` line endings when transmitted over SMTP. This issue has been addressed and users should upgrade to Postal v3.0.0 or higher. Once upgraded, Postal will only accept End of DATA sequences which are explicitly `<CR><LF>.<CR><LF>`. If a non-compliant sequence is detected it will be logged to the SMTP server log. There are no workarounds for this issue.

The La Banque Postale application before 3.2.6 for Android does not prevent the launching of an activity by a component of another application, which allows attackers to obtain sensitive cached banking information via crafted intents, as demonstrated by the drozer framework.

Buffer overflow in the UGameEngine::UpdateConnectingMessage function in the Unreal engine 1, 2, and 2.5, as used in multiple games including Unreal Tournament 2004, Unreal tournament 2003, Postal 2, Raven Shield, and SWAT4, when downloads are enabled, allows remote attackers to execute arbitrary code via a long LEVEL field in a WELCOME response to a download request.

The Unreal engine, as used in Unreal Tournament 3 1.3, Unreal Tournament 2003 and 2004, Dead Man's Hand, Pariah, WarPath, Postal2, and Shadow Ops, allows remote authenticated users to cause a denial of service (server exit) via multiple file downloads from the server, which triggers an assertion failure when the Closing flag in UnChan.cpp is set.

The Unreal Engine, as used in DeusEx 1.112fm and earlier, Devastation 390 and earlier, Mobile Forces 20000 and earlier, Nerf Arena Blast 1.2 and earlier, Postal 2 1337 and earlier, Rune 107 and earlier, Tactical Ops 3.4.0 and earlier, Unreal 1 226f and earlier, Unreal II XMP 7710 and earlier, Unreal Tournament 451b and earlier, Unreal Tournament 2003 2225 and earlier, Unreal Tournament 2004 before 3236, Wheel of Time 333b and earlier, and X-com Enforcer, allows remote attackers to execute arbitrary code via a UDP packet containing a secure query with a long value, which overwrites memory.